Pressure-controlled electric switch.



PATENTED JULY 12, 1904.

W. J. PUCH. PRESSURE CONTROLLER ELECTRIC SWITCH.

APPLICATION FILED NOV.16. 1903.

Z SHBETS-SHEETVL NO MODEL.

WTNESSES Attorneys No. 765,039. PATENTED JULY 12, 1904. W. J. PUGH.

PRESSURE GONTROLLED ELECTRIC lSWITCH.

APPLIOATION FILED NOV. 16, 1903'.

[Nl/ENTOR 0%- .00%. jg/(21M UNITED' STATES Patented July 12, i904.

PATENT Orricn.

IVILLIAM J. PUGH, OF DAVENPORT, IOVA, ASSIGNOR, BY DIRECT ANI) MESNE ASSIGNMENTS, TO AUTOMATIC ELEOTRICPUMP COMPANY OF DAVENPORT, IOWA.

PRESSURE-CONTROLLED ELECTREC SWiTCi-ii SPECIFICATION forming part of Letters' Patent No. 765,039, dated July I2, 1904. Application filed November 16, 1903. Serial No. 181.341 (No modelJ T0 @ZZ wtmn it iii/(ty concern:

Be it known/that I, IYILLIAM J.,PUGH, of Davenport, in the county of Scott and State of Iowa, have invented certain new and useful vImprovements in Pressure-Controlled Electric Switches; and I hereby declare that the following isa full, clear, and exact description thereof, reference being had to the accompanying drawings, which form part of this speciiication.

This invention is an improved automatic switch-controllerl or circuit maker'and breaker especially designed for use in connection with air-compressors actuated by electric motors and in which the switch is'operated by a pressure gage or indicator and when the pressure falls below a certain desired amount the electric circiiit is closed .and the motor started in operation pumping the air and when the desired pressure is obtained the circuit is broken by a snap action, so that danger of arcing is obviated.

I have shown the device in connection with an air-pressure gage; but the circuit making and breaking devices lare applicable to 'other kinds of gages having a rotatable indicatorfinger, and therefore I do not confine my in- Vention to use witlr air-compressors or airgages. i v

The novel features of the invention for which protection is desired are set forth in the claims, and I will now describe the invention with reference to the accompanying drawings, in which Figure l is a front view of the complete device as adapted to one form of air-compressing' apparatus. Fig. 2 is an enlarged view of the circuit making and breaking devices. Fig. 3 is a vertical section through Fig. 2. Fig. 4 1s adiagram of the apparatus,

showing the electrical connections.

In the drawings, A represents an electric motor of any desired type, on thc armatureshaft of which is a worm a, meshing with a worm-gear .7 o n a transverse shaft B, having opposite cranks C at its ends, respectively connected by pitmen c to pistons (Z within cylinders D, from which the compressed air may be conducted to a suitable reservoir R through pipes E, which connect with a prcssure-gage F by a branch e, as shown, said pressure-gage being of any desired construction and having a rotatable shaft f, carrying an indicator-finger G, which moves past the index g of the gage, as usual.

Within the gage-casing F', I place the circuit making and breaking devices, utilizing shaftf as a part thereof, said devices being constructed as follows:

On shaft f is fixed a linger H, which is adapted to make electrical contact with a metallic contact-piece I, attached to a ring O, preferably of non-conducting material, suspended in the casing by means of a threaded pin K, passing through a slotf' in the casing and provided with a thumb-nut on its outer end, by which means the ring can be rotatably v.adjusted in the casing and fixed when adjusted. The contact I has a lug which will catch the end of finger H as it moves backward, and thns close the circuit, as hereinafterdescribed.

Preferably inger H is insulated from shaft G, as shown, and to the hub of linger H is attached a spring L, which is bent into a long C shape, so as togiveitconsiderable elasticity andfreedom of movement within the ring O. The free end of spring L carries an armature of preferably soft iron, which is adapted to contact with the core j of an electromagnet J, which care may extend through the magnet and be fastened at its rear end to ring O, as shown, to support the magnet on the ring, and the magnet will always remain a uniform distance from contact I no matter in what position the ring O is adjusted. The core j in this instance is utilized as an electrical contact to make connection with spring L, said core being connected by a wire j' with the winding of the magnet J, the other terminal of which is connected by a wire J with a binding-post M, suitably located on but insulated froin the casing.

The contact-pieceI is similarly connected -by a. wire I with a binding-post N, attached to a suitablepoint on the casing. The binding-posts N M are respectively connected in. the motorc1rcu1t,'as indicated in Fig. 4, so

'that when the circuit is brokenA between thrown out of action;

spring L and magnet J bythe separationo farmature Zffrom core j' the motor will be Similarly, the motor will be thrown .out of action if contact is broken between finger VH and piece I. CBy properly adjusting ring O the device can be made to put the motor in operation whenever the pressure falls below'the desiredv point'by automatically closing the circuit.'l 'The magnet J,'moreover, is so'located on ring() that when finger H 1s resting against lug z' on piece i the armature Z is thrown into Contact with e core j and the'electrical circuit is' closed,'as

tially as described.

the armature Z and core j' will remain in contact until finger v has moved away `i'rom'lug but not entirely out of contact-therewithybut when it moves su ciently to overcome'lthe attraction between armature Z and core' j thel spring L snaps the armature quickly from `'the magnet, as indicated in dotted lines,"thusv breaking the circuit instantaneously without sparking. As the pressure in the gage lessens the linger G moves back toward the zero po,- sition and 1n so doing moves linger toward toward core y until conlug f1.7 and armature Z tact is made vbetween armature Z and core y,

which contact maybe hastened by residnary magnetism in the core and armature. soon as the Contact is made theelectric cn'- cuit is established and the motorwill runuu' til {inger H has moved sufciently away'fromy lug c' to cause the resilient pull `of* springljto snap armature Z from the magnet-core, which breaks the-,circuit instantaneously without sparking. Obviously theswitcli connections could be `utilized with steam or 'heatV gages if theycontain a rotatables'haft to which the finger H and springL can be attached.

Having thus described my invention, what I therefore cla/im as new, and desire to secureby Letters Patent thereon, is@v l. In combination, a contact-piece, an electromagnet, a rotatable shaft, a contact-finger attached to said shari, and adapted to make electrical contactwith the contact-piece.; and a spring attached to said shaft, adapted to make electrical contact with the electromag' net, substantially as described.`

2; In combination with a gage'rer indicator having a rotatable shaft, a contactfinger attached to said shaft adapted to make electrical contact with a contact; `and a spring attached to said shaft adapted'to make contact f with spring; said' contact-piece piecebeing xed on an Atric circuit, substantially pieces .being relatively "fixed but adjustable relatively to said finger and spring, substa'n 5. In' combination with a gage having a rotata-ble shaft, a 'conducting-iin'gerfand a cons. ducting-spring attached to said shaft, a con- .1 tact-piece adapted to. be contacted bysaid nger, vandanelectromagnet forming part ofthe electric circuit adapted to be contacted by said and said magnetadjustable support within the gage-casing, substantially as described.' v

' 6. In coinbinatioman electric ymotor and aira secondiconta'ct-piece adaptedto compressors actuatedthereby, and apressuregage havingv an indicating-finger mounted on a rotatable shaft; with a contact-finger and av contactspring on said shaft', a contact-piece v "adapted to be contacted by said finger, an electromagnetv adapted to be contacted by the spring, said vmagnet'forming'part of the elecas described.

7 ,The combination of an Aelectric motor, air-compressorsactuated thereby anda pressure-gage having an indicating-nger mounted on a rotatable shaft; with a contactftinger and a contact-spring on said shaita rotatable ring within the casin ,`gl surrounding said nger and spring,'a 'contact-niece on said ring adapted to be contacted .by said nger, ankelecy tromagnet on said' ring adapted to be contacted by the spring, said magnet forming part of the electric circuit, and means for adjusting said ring, sub stantiallyas and im? the purpose described.

'-n testimony that claimtheiforegoing as 'my own aiiix my signature `in presence of two witnesses. v

WLLiAli/.i J. PUGH. In presence of,

NEAL,

D. M. TAYLOR.' 

